Chuck for screw-machines



(No Model.)

C. M. lNRADSON.- y CHUCK P0 CREW MACHINES.

No. 489,933. Patented Jan. 17, 1893.

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CONRAD M. COA/RADSUN,

STATES Arnim* rricn.

' ACHUCK FOR SCREWi-IVIACHINES.

SPECIFICATION forming part of Letters Patent N0. 489,933, dated January17, 1893.

Application led March 24,1892. Serial No. 426,251. (No model.)

To @ZZ whom it may concern.v Beit known that I, CONRAD M. OoNRADsoN,

. a citizen of the United States, residing at Madison, in the county ot'Dane and State of Wiseonsin, have invented certain new and usefulImprovements in Chucks for Screw-Machin es, of which the following is aspecilication.

My invention relates to chucks or workholders, and has reference moreparticularly to that class of chucks used on screw making machines,although the invention is obviously applicable to other classes andstyles of machinery.

In the accompanying drawings, Figure l is a side elevation partly insection of my improved chuck, and the mechanism for operating the sameas applied to the head stock of a screw making lathe; Fig. 2, front endView of the same; and Fig. 3, an enlarged longitudinal sectional viewthrough the chuck proper.

A indicates the head stock of a lathe, B, the hollow arbor or mandrel,and O the chuck secured to the end thereof. This chuck comprises a mainbody or tubular stem D, having at a distance from its ends a collar E,and at its outer end a conical socket F, as clearly shown in Fig. 3.Mounted in this socket F is a conical split ring G made up of two ormore sections and having its outer end shouldered or reduced slightly toreceive a ring I-I which is threaded externally as shown in Fig. 8 toengage the sliding shell or case I of the chuck. This sliding shell orcase I is provided with a number of sockets J extending parallel withthe axis of the arbor, and in eachvof these sockets I mount a coiledspring K, which bears at one end against the base of the socket and atthe opposite end against the head of a screw or bolt L whose inner end,passing through the bottom wall of the socket, screws into the collar orflange E of the tubular stem D. These springs tend to draw the slidingbody I rearwardly with reference to the tubular stem, and as this body Imoves rearwardly it will, through the collar II which is connectedthereto, cause the slotted conical collar or ring G to tightly grasp therod or other article passing through the hollow stem of the chuck. Itwill therefore be seen that the grip action in` this case is dueentirely and solely to the action of the springs, and as there is quitea large number of these springs they will act effectively to clamp therod in position. In order to release the rod which passes through thetubular stem it is necessary to move the shell I outward against thepressure of the springs so that the sections of the slotted block G maybe freed to permit the rod tobe readily passed through the tubular stemD. In order to thus move or actuate the shell I, I employ a lever Mwhich is pivoted to an arm N projecting from the upper side of the headstock. This lever M is made in the form of a yoke to encircle thesliding chuck shell I and is provided with a ring Q which is fitted intoa circumferential groove P formed in the shell I as clearly shown inFig. l. The ring Q is pivotally connected with the yoke or lever M bymeans ot' the pivots or studs O, as shown in Fig. 2. The lower end ofthe yoke or lever M comes directly opposite the outer end of a piston Rwhich is mounted in a cylinder S, formed, in the present instance, inthe head stock of the machine; the said piston being designed to beactuated by air, water, gas, steam or other iiuid admitted to thecylinder through the inlet pipe T.

The inlet pipe 'F communicates with a chamber U which communicatesthrough a passage d with a chamber V, which latter communicates directlywith the cylinder S. The chamber V also communicates with a chamber W bymeans of a passage b and the said chamber W is connected to the outletpipe X as clearly shown in Fig. l.

Y indicates a vertically moving valve which has its seat in the passagea, and when raised, opens communication between the chambers U andV,-the lower end of said valve Y being supported upon a lever Z pivotedto an arm or bracket c projecting from the frame of the machine. Acoiled spring d encircles the lower end of the valve-rod and by bearingat opposite ends against the lower stuffing box and a washer or collaron the valve rod, tends to hold the valve to its seat. When, therefore,it is desired to actuate the piston R it is only necessary to raise upthe rear end of the lever Z and thereby raise the valve from its seat.This being done, the iiuid iinds its way through the pipe 'll`, chamberU and passage d into chamber V and from this chamber into the cylinder.The

fluid then acts upon the rear end of the piston R, projects the samefrom the cylinder and carries the yoke or lever M forwardly and withitthe shell I of the chuck.

In order to provide for the inward or return movement of the piston Iemploy a second valve, A which passes vertically through the passage ZJand is, like the Valve Y, provided with a coiled spring d. rIhe lowerend of this valve A also rests upon one end ot" the lever Z, and henceit is only necessary to raise that end of the lever to cause the valveto rise from its seat. As soon as the valve rises from its seat the'fluid passes from the cylinder into the chamber V down through thepassage b into chamber NV and out through the pipe X, the pressure ofthe springs K in the chuck being sufficient to throw the lever andpiston back into the cylinder and force the tluid from the cylinder.

It is obvious that the chuck represented in Fig. 3 may be actuated bymeans other than those shown in Fig. l; and it is also clear t-hat theconstruction and arrangement of the Valve mechanism shown in Fig. l canbe used in combination with other vstyles of chuck. Forinstance, thosechucksin which the lever or yoke M would serve to grip or tighten thejaws instead of releasing them as in the present instance.

While I have for convenience shown the valve chambers and the cylinderas mounted directly in the head stock of the lathe, this is notessential.

I am aware that achuck has been patented in which the hollow stem wasfashioned into a piston and mounted within a rotating cylinder, and tosuch construction I make no claim.

Having thus described my invention, what I claim iszl. In a chuck, thecombination with a hol low stem having aconical socket at its outer end,of a conical collar seated in said socket, asliding shell mounted uponthe tubular stem, springs serving to urge the shell backward and toforce the conical block against the article to be held, and means formoving the shell forward.

2. In combination with a tubular body D having a conical socket F at itsouter end, the conical slotted collar G mounted in the socket, a ring IIapplied to the face of said collar, a sliding shell mounted upon thebody ot the chuck and connected with the ring Il,

a series of bolts L mounted in suitable sockets in the shell I andsecured to the body of the chuck, and coiled springs K encircling saidbolts and serving to move the shell I i11- wardly or backward upon themain body of the chuck.

3. In combination with the tubular body D, the conical collar G, thesliding shell I, the springs serving to actuate the shell and force thecollar against the article, and the yoke or lever M for moving saidshell I outward against the force of the spring, all substantially asshown and described.

4. In combination with the chuck provided with a series of jaws,springsserving to actuate said jaws and cause them to bind upon the article tobe grasped, and iiuid pressure mechanism to overcome the tension of saidsprings and release the jaws.

5. ln combination with a sliding portion or member of a chuck, anindependent iiuid pressure mechanism, substantially as shown anddescribed, for actuating said sliding member.

6. In combination with a chuck and the actuating lever or yoke M,acylinder provided with a piston R to act upon the end of the yoke orlever, a valve Y for admitting fluid under pressure to said cylinder,and an outlet valve A', all combined and arranged for operation,substantially as described.

7. In combination with achuck and its operating lever M, a cylinder Sprovided With a piston R, an inlet chamber U, an outlet chamber WV, anintermediate chamberV connected with the cylinder and communicating withthe chambers U and W respectively, by passages d and l), a valve Ymounted in the passage a, and a valve A .mounted in the passage b, allsubstantially as shown and described.

8. In combination with a chuck and its actuating lever M, a cylinder Sprovided with piston R, an inlet valve Y and an outlet valve A', springsencircling the valve stems and serving to hold them to their seats, anda lever Z upon which the valves rest, all substantially as shown anddescribed.

In witness whereof I hereunto set my hand in the presence of twowitnesses.

CONRAD M. CONRADSON.

Witnesses:

J oHN F. LYDoN, W. R. BAGLEY.

IOO

